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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-06-19 21:00:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-06-19 21:00:30 +0000 |
commit | e54def4ad8144ab15f826416e2e0f290ef1901b4 (patch) | |
tree | 583f8d4bd95cd67c44ff37b878a7eddfca9ab97a /tools/perf/util/bpf_lock_contention.c | |
parent | Adding upstream version 6.8.12. (diff) | |
download | linux-e54def4ad8144ab15f826416e2e0f290ef1901b4.tar.xz linux-e54def4ad8144ab15f826416e2e0f290ef1901b4.zip |
Adding upstream version 6.9.2.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/perf/util/bpf_lock_contention.c')
-rw-r--r-- | tools/perf/util/bpf_lock_contention.c | 124 |
1 files changed, 122 insertions, 2 deletions
diff --git a/tools/perf/util/bpf_lock_contention.c b/tools/perf/util/bpf_lock_contention.c index 31ff19afc2..b4cb3fe5cc 100644 --- a/tools/perf/util/bpf_lock_contention.c +++ b/tools/perf/util/bpf_lock_contention.c @@ -179,6 +179,123 @@ int lock_contention_prepare(struct lock_contention *con) return 0; } +/* + * Run the BPF program directly using BPF_PROG_TEST_RUN to update the end + * timestamp in ktime so that it can calculate delta easily. + */ +static void mark_end_timestamp(void) +{ + DECLARE_LIBBPF_OPTS(bpf_test_run_opts, opts, + .flags = BPF_F_TEST_RUN_ON_CPU, + ); + int prog_fd = bpf_program__fd(skel->progs.end_timestamp); + + bpf_prog_test_run_opts(prog_fd, &opts); +} + +static void update_lock_stat(int map_fd, int pid, u64 end_ts, + enum lock_aggr_mode aggr_mode, + struct tstamp_data *ts_data) +{ + u64 delta; + struct contention_key stat_key = {}; + struct contention_data stat_data; + + if (ts_data->timestamp >= end_ts) + return; + + delta = end_ts - ts_data->timestamp; + + switch (aggr_mode) { + case LOCK_AGGR_CALLER: + stat_key.stack_id = ts_data->stack_id; + break; + case LOCK_AGGR_TASK: + stat_key.pid = pid; + break; + case LOCK_AGGR_ADDR: + stat_key.lock_addr_or_cgroup = ts_data->lock; + break; + case LOCK_AGGR_CGROUP: + /* TODO */ + return; + default: + return; + } + + if (bpf_map_lookup_elem(map_fd, &stat_key, &stat_data) < 0) + return; + + stat_data.total_time += delta; + stat_data.count++; + + if (delta > stat_data.max_time) + stat_data.max_time = delta; + if (delta < stat_data.min_time) + stat_data.min_time = delta; + + bpf_map_update_elem(map_fd, &stat_key, &stat_data, BPF_EXIST); +} + +/* + * Account entries in the tstamp map (which didn't see the corresponding + * lock:contention_end tracepoint) using end_ts. + */ +static void account_end_timestamp(struct lock_contention *con) +{ + int ts_fd, stat_fd; + int *prev_key, key; + u64 end_ts = skel->bss->end_ts; + int total_cpus; + enum lock_aggr_mode aggr_mode = con->aggr_mode; + struct tstamp_data ts_data, *cpu_data; + + /* Iterate per-task tstamp map (key = TID) */ + ts_fd = bpf_map__fd(skel->maps.tstamp); + stat_fd = bpf_map__fd(skel->maps.lock_stat); + + prev_key = NULL; + while (!bpf_map_get_next_key(ts_fd, prev_key, &key)) { + if (bpf_map_lookup_elem(ts_fd, &key, &ts_data) == 0) { + int pid = key; + + if (aggr_mode == LOCK_AGGR_TASK && con->owner) + pid = ts_data.flags; + + update_lock_stat(stat_fd, pid, end_ts, aggr_mode, + &ts_data); + } + + prev_key = &key; + } + + /* Now it'll check per-cpu tstamp map which doesn't have TID. */ + if (aggr_mode == LOCK_AGGR_TASK || aggr_mode == LOCK_AGGR_CGROUP) + return; + + total_cpus = cpu__max_cpu().cpu; + ts_fd = bpf_map__fd(skel->maps.tstamp_cpu); + + cpu_data = calloc(total_cpus, sizeof(*cpu_data)); + if (cpu_data == NULL) + return; + + prev_key = NULL; + while (!bpf_map_get_next_key(ts_fd, prev_key, &key)) { + if (bpf_map_lookup_elem(ts_fd, &key, cpu_data) < 0) + goto next; + + for (int i = 0; i < total_cpus; i++) { + update_lock_stat(stat_fd, -1, end_ts, aggr_mode, + &cpu_data[i]); + } + +next: + prev_key = &key; + } + free(cpu_data); +} + int lock_contention_start(void) { skel->bss->enabled = 1; @@ -188,6 +305,7 @@ int lock_contention_start(void) int lock_contention_stop(void) { skel->bss->enabled = 0; + mark_end_timestamp(); return 0; } @@ -210,7 +328,7 @@ static const char *lock_contention_get_name(struct lock_contention *con, /* do not update idle comm which contains CPU number */ if (pid) { - struct thread *t = __machine__findnew_thread(machine, /*pid=*/-1, pid); + struct thread *t = machine__findnew_thread(machine, /*pid=*/-1, pid); if (t == NULL) return name; @@ -301,8 +419,10 @@ int lock_contention_read(struct lock_contention *con) if (stack_trace == NULL) return -1; + account_end_timestamp(con); + if (con->aggr_mode == LOCK_AGGR_TASK) { - struct thread *idle = __machine__findnew_thread(machine, + struct thread *idle = machine__findnew_thread(machine, /*pid=*/0, /*tid=*/0); thread__set_comm(idle, "swapper", /*timestamp=*/0); |